ESRL Global Systems Division
High-Resolution Rapid Refresh Domain Now Expanded
As of 25 March 2009, the High-Resolution Rapid Refresh (HRRR), an hourly 3-km convective-scale model initialized from the radar-assimilating Rapid Update Cycle (RUC), began running over a larger horizontal domain covering the eastern 2/3 of the contiguous United States.
The radar-reflectivity assimilation technique developed at ESRL was implemented by NCEP and ESRL last November into the operational 13-km RUC, the first model at NCEP with reflectivity assimilation. The 3-km HRRR relies on the RUC reflectivity assimilation to accurately predict ongoing convection and assimilation of aircraft, satellite, profiler, surface, GPS moisture, etc. to predict the mesoscale storm environment. The HRRR uses a version of the WRF model, a community mesoscale model, including some components developed by ESRL. Twelve-hour HRRR forecasts over this larger domain are run in 42 min every hour on the ESRL supercomputer using 480 cores supported by the FAA and NOAA.
ESRL can now evaluate real-time HRRR forecasts through this spring and summer over this larger area to include the Central US. In partnership with NCAR, NCEP, MIT/LL, FAA, NOAA's Storm Prediction Center and Aviation Weather Center, ESRL will continue to improve assimilation and modeling techniques toward achieving NOAA's goals to provide accurate county-scale severe weather forecasts hours in advance and improve aviation guidance.
Name: Stan Benjamin